Contactless ignition system for internal combustion engines

ABSTRACT

A contactless ignition system for internal combustion engines comprising: at least one charging circuit including a series combination of a capacitor charging coil for generating an output by the rotation of a permanent magnet, rectifying means for rectifying the generated output of the capacitor charging coil and a capacitor, with the flow of current being directed from the capacitor charging coil to the capacitor through said rectifying means; at least one discharging circuit including a series combination of said capacitor and a thyristor having a gate to cause said capacitor to discharge its stored charge upon conduction of said thyristor; at least one ignition coil having a primary winding and a secondary winding; and at least one transformer having at least one primary winding and secondary winding, respectively, with the primary winding electrically connected to said capacitor charging coil to thereby detect the generated output thereof, wherein the primary winding of said ignition coil is connected in series in said discharging circuit, wherein at least one spark plug is connected to the secondary winding of said ignition coil, and wherein the secondary winding of said transformer is electrically connected to the gate of said thyristor.

United States Patent 1191 Nagasawa [451 May 7,1974

[ CONTACTLESS IGNITION SYSTEM FOR [73] Assignee: Nippondenso Co., Ltd., Kariya-shi,

Japan 22 Filed: Oct. 20, 1972 21 Appl. No.: 299,452

[30] Foreign Application Priority Data Prir nary ExaminerLaurence M. Goodridge ,AsstsmntoEz m ne R n 3- C93 Attorney, Agent, or Firm-Cushman, Darby & Cushman 5 7] ABSTRACT A contactless ignition system for internal combustion engines comprising: at least one charging circuit including a series combination of a capacitor charging coil for generating an output by the rotation of a permanent magnet, rectifying means for rectifying the generated output of the capacitor charging coil and a capacitor, with the-flow of current being directed from the capacitor charging coil to the capacitor through said rectifying means; at least one discharging circuit including a series combination of said capacitor and a thyristor having a gate to cause said capacitor to dis- I charge its storedcharge upon conduction of said thyristor; at least one ignition coil having a primary winding and a secondary winding; and at least one transformer having at least one primary winding and secondary winding, respectively, with the primary winding electrically connected to said capacitor charging coil to thereby detect the generated output thereof, wherein the primary winding of said ignition coil is connected in series in said discharging circuit, wherein at least one spark plug is connected to the secondary winding of said ignition coil, and wherein the secondary winding of said transformer is electrically connected to the gate of said thyristor.

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1. An ignition system for internal combustion engines comprising: at least one charging circuit including a series combination of a capacitor charging coil for generating an output by the rotation of a permanent magnet, rectifying means for rectifying the generated output of said capacitor charging coil, and a capacitor, the flow of current in said charging circuit being directed from said capacitor charging coil to said capacitor through said rectifying means; at least one discharging circuit including said capacitor and a thyristor having a gate and connected in series with said capacitor so that said capacitor is caused to discharge its stored charge upon conduction of said thyristor; at least one ignition coil having a primary winding and a secondary winding; and at least one transformer having at least one primary winding and one secondary winding with said primary winding being electrically connected to said capacitor charging coil to detect the generated output thereof, wherein the primary winding of said ignition coil is connected to form said discharging circuit, wherein at least one spark plug is connected to the secondary winding of said ignition coil, and wherein the secondary winding of said transformer is electrically connected to the gate of said thyristor.
 2. An ignition system for internal combustion engines comprising: a plurality of charging circuits each thereof including a series combination of a capacitor charging coil for generating an output by the rotation of a permanent magnet, rectifying means for rectifying the generated output of said capacitor charging coil, and a capacitor, the flow of current in each said charging circuit being directed from said capacitor charging coil to said capacitor through said rectifying means; a plurality of discharging circuits each thereof including said capacitor in one of said plurality of charging circuits and a thyristor having a gate and connected in series with said capacitor so that said capacitor is caused to discharge its stored charge upon conduction of said thyristor; a plurality of ignition coils each thereof having a primary winding and a secondary winding; and a plurality of transformers each thereof having at least one primary winding and secondary winding with said primary winding being electrically connected to one of said capacitor charging coils associated therewith to detect the generated output thereof, wherein the primary winding of each of said plurality of ignition coils is connected to form one of said plurality of discharging circuits associated therewith, wherein at least one spark plug is connected to the secondary winding of said each ignition coil, and wherein the secondary winding of said each transformer is electrically connected to the gate of the thyristor in one of said plurality of discharging circuits associated with one of said plurality of charging circuits in which the capacitor charging coil is not electrically connected to the pRimary winding associated with said secondary winding.
 3. An ignition system for internal combustion engines comprising: a first charging circuit including a series combination of a first capacitor charging coil for generating an output by the rotation of a permanent magnet, first rectifying means for rectifying the generated output of said capacitor charging coil, a capacitor, and a first thyristor having a gate to control the charging and discharging of said capacitor, the flow of current in said first charging circuit being directed from said first capacitor charging coil to said first thyristor through said first rectifying means and said capacitor; a second charging circuit including a series combination of a second capacitor charging coil for generating an output by the rotation of a permanent magnet, second rectifying means for rectifying the generated output of said second capacitor charging coil, said capacitor and a second thyristor having a gate to control the charging and discharging of said capacitor, the flow of current in said second charging circuit being directed from said second capacitor charging coil to said second thyristor through said second rectifying means and said capacitor to charge said capacitor in opposition to the polarity with which said capacitor is charged by said first charging circuit; a first discharging circuit including a series combination of said capacitor, said first thyristor and a first diode to discharge the charge stored in said capacitor by said second charging circuit through said first thyristor and said first diode; a second discharging circuit including a series combination of said capacitor, said second thyristor and a second diode to discharge the charge stored in said capacitor by said first charging circuit through said second thyristor and said second diode; first and second transformers each thereof having at least one primary winding and secondary winding the primary windings of said first and second transformers being respectively electrically connected to said first and second capacitor charging coils to detect the generated outputs thereof; and first and second ignition coils each thereof having a primary winding and a secondary winding, wherein the primary windings of said first and second ignition coils are respectively connected to form said first and second discharging circuits, wherein at least one spark plug is connected to the secondary winding of said first and second ignition coils, respectively, and wherein the secondary windings of said first and second transformers are respectively electrically connected to the gates of said first and second thyristors.
 4. An ignitin system according to claim 1, wherein the primary winding of said transformer is connected in parallel with said capacitor charging coil, and wherein a diode is connected in series with the primary winding of said transformer to pass therethrough only those half voltage waves of said capacitor charging coil which are opposite in polarity to the charging half voltage waves thereof.
 5. An ignition system according to claim 2, wherein, in said each charging circuit, the primary winding of said transformer is connected in parallel with said capacitor charging coil, and wherein a diode is connected in series with said primary winding of said transformer to pass therethrough only those half voltage waves of said capacitor charging coil which are opposite in polarity to the charging half voltage waves thereof.
 6. An ignition system according to claim 3, wherein the primary windings of said first and second transformers are respectively connected in parallel with said first and second capacitor charging coils, and wherein the primary windings of said first and second transformers are respectively connected in series with diodes, so that only those half voltage waves of said first and second capacitor charging coils, which are opposite in polarity to the charging half voltage waves thereof, may pass through said diodes.
 7. An ignition System according to claim 1, wherein said transformer consists of a current transformer having its primary winding connected to form said charging circuit.
 8. An ignition system according to claim 2, wherein, in each said charging circuit, said transformer consists of a current transformer having its primary winding connected to form said charging circuit.
 9. An ignition system according to claim 1, wherein said capacitor charging coil consists of two coil portions connected in such a manner that the respective voltages induced in said coil portions are added together, wherein the primary winding of said transformer is connected in parallel with one of said coil portions, and wherein a diode is connected in series with the primary winding of said transformer to pass therethrough only those half voltage waves of said coil portions which are opposite in polarity to the charging half voltage waves thereof.
 10. An ignition system according to claim 2, wherein, in each said charging circuit, said capacitor charging coil consists of two coil portions connected in such a manner that respective voltages induced in said coil portions are added together, wherein the primary winding of said transformer is connected in parallel with one of said coil portions, and wherein a diode is connected in series with the primary winding of said transformer to pass therethrough only those half voltage waves of said coil portions which are opposite in polarity to the charging half voltage waves thereof.
 11. An ignition system according to claim 3, wherein each of said first and second capacitor charging coils comprises two coil portions connected in such a manner that respective voltages induced in said two coil portions are added together, wherein the primary winding of each of said first and second transformers is connected in parallel with one of said two coil portions associated therewith, and wherein a diode is connected in series with the primary winding of each of said first and second transformers to pass therethrough only those half voltage waves of said coil portions which are opposite in polarity to the charging half voltage waves thereof.
 12. An ignition system according to claim 9, wherein said two coil portions of said capacitor charging coil are wound on one and the same core with the first coil portion having a higher number of turns than that of the second coil portion, and wherein the primary winding of said transformer is connected in parallel with said second coil portion of said capacitor charging coil.
 13. An ignition system according to claim 10, wherein said two coil portions of said capacitor charging coil are wound on one and the same core with the first coil portion having a higher number of turns than that of the second coil portion, and wherein the primary winding of said transformer is connected in parallel with said second coil portion of said capacitor charging coil.
 14. An ignition system according to claim 11, wherein said two coil portions of said first and second capacitor charging coils are respectively wound on one and the same core with the first coil portion having a higher number of turns than that of the second coil portion, wherein the primary windings of said first and second tranformers are respectively connected in parallel with said second coil portions of said first and second capacitor charging coils.
 15. An ignition system according to claim 9, wherein said coil portions of said capacitor charging coil are wound on separate magnetically parallel cores with the first coil portion having a higher number of turns than that of the second coil portion, and wherein the primary winding of said transformer is connected in parallel with said first coil portion.
 16. An ignition system according to claim 10, wherein said coil portions of said capacitor charging coil are wound on separate magnetically parallel cores with the first coil portion having a high number of turns than that of the second coil portion, and wherein the primary winding Of said transformer is connected in parallel with said first coil portion of said capacitor charging coil.
 17. An ignition system according to claim 11, wherein said coil portions of said first and second capacitor charging coils are respectively wound on separate magnetically parallel cores with the first coil portion having a higher number of turns than that of the second coil portion, and wherein the primary windings of said first and second transformers are connected in parallel with said first coil portions of said first and second capacitor charging coils. respectively.
 18. An ignition system according to claim 2, wherein, in each said charging circuit, the primary winding of said transformer consists of first and second winding portions, wherein said first winding portion is connected to form said charging circuit between said capacitor charging coil and said rectifying means and said second winding portion is connected in parallel with said capacitor charging coil, wherein a diode is connected in series with said second winding portion to pass therethrough only those half voltage waves of said capacitor charging coil which are opposite in polarity to the charging half voltage waves thereof, and wherein said first and second winding portions of said transformer primary winding are arranged to induce voltages of the same polarity in the secondary winding of said transformer.
 19. An ignition system according to claim 8, wherein the primary winding of said current transformer is provided with a center tap, wherein one end of said primary winding is connected to one end of said capacitor charging coil through the cathode and the anode of a first diode and the other end of said primary winding is connected to said one end of said capacitor charging coil through the anode and the cathode of a second diode, and wherein said center tap is connected to the other end of said capacitor charging coil through the cathode and the anode of a third diode.
 20. An ignition system according to claim 8, wherein the primary winding of said current transformer is connected between one end of said capacitor charging coil and said rectifying means, wherein the secondary winding of said current transformer is provided with a center tap which divides said secondary winding into a first portion having a large number of turns and a second portion having a small number of turns, wherein the ends of said transformer secondary winding are interconnected through respective diodes and the junction point of said ends is electrically connected to the gate of said thyristor, wherein said center tap is connected to the cathode of said thyristor, and wherein the junction point between the primary winding of said current transformer and said rectifying means is connected to the other end of said capacitor charging coil through the cathode and the anode of a diode.
 21. An ignition system according to claim 8, wherein, in each said charging circuit, said rectifying means consist of four rectifying diodes for subjecting an AC output of said capacitor charging coil to full-wave rectification and supplying the resultant rectified output to the primary winding of said current transformer and said capacitor.
 22. An ignition system according to claim 8, wherein, in each of said charging circuits, the secondary winding of said current transformer is provided with a center tap, wherein one end of said secondary winding is connected to the gate of said thyristor through a rectifying diode and the other end of said secondary winding is connected to the gate of said thyristor through a rectifying diode and an adjusting resistor, and wherein said center tap is connected to the cathode of said thyristor.
 23. An ignition system according to claim 18, wherein said first primary winding portion of said transformer has a higher number of turns than that of said second primary winding portion.
 24. An ignition system according to claim 8, wherein, in each of said charging circuits, the ends of said capacitor charging coil are connected to one end of the primary winding of said current transformer through the anode and the cathode of respective diodes, and wherein the other end of the primary winding of said current transformer is connected to one end of said capacitor charging coil through a resistor and the anode and the cathode of a diode.
 25. An ignition system according to claim 8, wherein when a capacitor charging current flows in one of said plurality of charging circuits, the thyristors in at least two of said plurality of discharging circuits associated with the others of said plurality of charging circuits are controlled. 26, An ignition system according to claim 8, wherein, in each of said charging circuits, said current transformer comprises one primary winding and two secondary windings, wherein said two secondary windings are electrically connected to the respective thyristors in two different ones of said plurality of discharging circuits, and wherein when a capacitor charging current flows in one of said plurality of charging circuits, the thyristors in two of said plurality of discharging circuits associated with the others of said plurality of charging circuits are controlled.
 27. An ignition system according to claim 8, wherein, in each of said charging circuits, the ends of said capacitor are interconnected through a resistor having a high resistance value to complete a closed circuit, and wherein the charge stored in said capacitor is discharged through said high resistance resistor.
 28. An ignition system according to claim 2, wherein, in each of said charging circuits, said capacitor charging coil is connected through the primary winding of said transformer and an engine stopping switch to the capacitors in the others of said charging circuits.
 29. An ignition system according to claim 6, wherein the output voltages of the secondary windings of said first and second transformers are respectively rectified through full-wave rectifiers each thereof having four diodes, and wherein the output terminals of said secondary windings are connected so as to supply control voltages to the respective gates of said first and second thyristors.
 30. An ignition system according to claim 6, wherein the ends of the secondary windings of said first and second transformers are respectively interconnected through respective rectifying diodes and the interconnections are respectively electrically connected to the gates of said first and second thyristors, and wherein the center points of the respective secondary windings of said first and second transformers are electrically connected to the respective cathodes of said first and second thyristors.
 31. An ignition system according to claim 6, wherein each of said first and second thyristors consists of a bidirectional thyristor, and wherein the AC outputs of the respective secondary windings of said first and second transformers are applied to the respective gates of said first and second thyristors.
 32. An ignition system according to claim 9, wherein, in the same polarity with that of said diode, a rectifying diode is connected in parallel with a series circuit consisting of said coil portions connected in parallel with the primary winding of said transformer and said rectifying means.
 33. An ignition system according to claim 9, wherein a diode for passing only those half voltage waves of said two coil portions of said capacitor charging coil which are opposite in polarity to the charging half voltage waves thereof is connected in parallel with one of said two coil portions which is not connected in parallel with the primary winding of said transformer.
 34. An ignition system according to claim 10, wherein, in each of said charging circuits, a diode for passing only those half voltage waves of said capacitor charging coil portions which are opposite in polarity to the charging half voltage waves thereof, is connected in parallel with one of said coil portions which is not connected in parallel with the primary winding of said transformer.
 35. An ignition system according to claim 11, wherein diodes are connected in parallel with said coil portions of said first and second capacitor charging coils, respectively, which coil portions are not connected in parallel with the primary windings of said first and second transformers, respectively, said diodes passing only those half voltage waves which are opposite in polarity to the charging half voltage wave of said coil portions of said first and second capacitor charging coils.
 36. An ignition system according to claim 4, wherein in parallel with a portion of said capacitor charging coil, there is connected a diode for passing only those half voltage waves of said coil portion which are opposite in polarity to the charging half voltage waves thereof.
 37. An ignition system according to claim 5, wherein, in each of said charging circuits, there is connected, in parallel with a portion of said capacitor charging coil, a diode for passing only those half voltage waves of said coil portion which are opposite in polarity to the charging half voltage waves thereof.
 38. An ignition system according to claim 6, wherein there are connected in parallel with portions of said first and second capacitor charging coils, respectively, a diodes for passing only those half voltage waves which are opposite in polarity to the charging half voltage waves of said coil portions.
 39. An ignition system according to claim 9, wherein a diode is connected in parallel with said capacitor charging coil to pass only those half voltage waves of said capacitor charging coil which are opposite in polarity to the charging half voltage waves thereof.
 40. An ignition system according to claim 10, wherein a diode is connected in parallel with each of said capacitor charging coils to pass only those half voltage waves of said capacitor charginf coil which are opposite in polarity to the charging half voltage waves thereof.
 41. An ignition system according to claim 11, wherein a diode is connected in parallel with each of said first and second capacitor charging coils to pass only those half voltage waves of each cpacitor charging coil which are opposite in polarity to the charging half voltage waves thereof.
 42. An ignition system according to claim 12, wherein, in parallel with said first coil portion of said capacitor charging coil having a higher number of turns, there is connected a diode for passing only those half voltage waves of said first coil portion which are opposite in polarity to the charging half voltage waves thereof.
 43. An ignition system according to claim 13, wherein, in parallel with said first coil portion of each of said capacitor charging coils having a higher number of turns, there is connected a diode for passing only those half voltage waves of said first coil portion which are opposite in polarity to the charging half voltage waves thereof.
 44. An ignition system according to claim 14, wherein, in parallel with said first coil portion with a higher number of turns of each of said first and second capacitor charging coils, there is connected a diode for passing only those half voltage waves of said first coil portion which are opposite in polarity to the charging half voltage waves thereof.
 45. An ignition system according to claim 15, wherein, in parallel with said second coil portion of said capacitor charging coil having a smaller number of turns, there is connected a diode for passing only those half voltage waves of said second coil portion which are opposite in polarity to the charging half voltage waves thereof.
 46. An ignition system according to claim 16, wherein, in parallel with said second coil portion with a smaller number of turns of each of said capacitor charging coils, there is connected a diode for passing only those half voltage waves of said second coil portion which are opposite in polarity to the charging half voltage waves thereof.
 47. An ignition system according to claim 17, wherein, in parallel with said second coil portion with a smaller number of turns of each of said first and second capacitor charging coils, there is connected a diode for passing only those half voltage waves of said second coil portion which are opposite in polarity to the charging half voltage waves thereof.
 48. An ignition system for internal combustion engines comprising: a first charging circuit including a series combination of a capacitor charging coil for generating an output by the rotation of a permanent magnet, first rectifying means for rectifying the generated output of said capacitor charging coil, and a first capacitor, the flow of current in said first charging circuit being directed from one end of said capacitor charging coil to said first capacitor through said first rectifying means; a second charging circuit including a series combination of said capacitor charging coil, second rectifying means for rectifying the generated output of said capacitor charging coil, and a second capacitor, the flow of current in said second charging circuit being directed from the other end of said capacitor charging coil to said second capacitor through said second rectifying means; a first discharging circuit including a series combination of said first capacitor and a first thyristor having a gate to cause said first capacitor to discharge its stored charge upon conduction of said first thyristor; a second discharging circuit including a series combination of said second capacitor and a second thyristor having a gate to cause said second capacitor to discharge its stored charge upon conduction of said second thyristor; first and second ignition coils each thereof having a primary winding and a secondary winding; and first and second transformers each thereof having a primary winding and a secondary winding, said primary windings being electrically connected to said capacitor charging coil to detect the generated output thereof, wherein the primary windings of said first and second ignition coils are respectively connected to form said first and second discharging circuits, wherein at least one spark plug is connected to each of the secondary windings of said first and second ignition coils, and wherein the secondary windings of said first and second transformers are electrically connected to the respective gates of said first and second thyristors. 